The use of immunoglobulins as therapeutic agents has increased dramatically in recent years and have expanded to different areas of medical treatments. Such uses include treatment of agammaglobulinemia and hypogammaglobulinemia, as immunosuppressive agents for treating autoimmune diseases and graft-vs.-host (GVH) diseases, the treatment of lymphoid malignancies, and passive immunotherapies for the treatment of various systemic and infectious diseases. Also, immunoglobulins are useful as in vivo diagnostic tools, for example, in diagnostic imaging procedures.
One critical issue in these therapies is the persistence of immunoglobulins in the circulation. The rate of immunoglobulin clearance directly affects the amount and frequency of dosage of the immunoglobulin. Increased dosage and frequency of dosage may cause adverse effects in the patient and also increase medical costs. Further, immunoglobulin preparations often have short shelf lives and may lose biological activity of the antibodies resulting from chemical and physical instabilities during the storage and shipment, which decreases the effectiveness of these molecules and results in manufacturing waste.
Thus, there is in a need in the pharmaceutical industry for immunoglobulin molecules with increased storage stability and/or increased in vivo half-lives.